1. Field of the Invention
The present invention relates to devices used in well completions and, more particularly, to a device to prevent a pump-out plug which has been released from interfering with well completion operations.
2. Setting of the Invention
After a wellbore has been drilled, various wellbore completion operations can be initiated to make the wellbore suitable for production of hydrocarbons or the like. In certain situations it is desirable for the wellbore to be completed so fluids from two or more producing zones can be commingled and removed together from the wellbore. When the two fluids are to be produced the producing zones can segregated by at least one retrievable bridge plug assembly which is set within the wellbore between the two producing zones by a wireline or set via a tubing string. When completing a wellbore in this manner a packer assembly with a pump out plug can be used to isolate formation pressures in the wellbore from the surface so the tubing can be run into the wellbore freely without having to overcome the force of the bottomhole reservoir pressure. The packer assembly generally consists of a packer and a seating nipple with a removable pump out plug seated in the nipple.
When the bridge plug assembly is to removed from the wellbore, a tubing string is lowered into the wellbore and connected to a threaded neck of the bridge plug assembly and then is removed. While this operation is usually simple and efficient, problems can arise in retrieving the bridge plug when packer assembly is set above the retrievable bridge plug assembly. In this case, a tubing string is connected to the packer, and fluid is introduced through the tubing to force the pump-out plug out from the packer assembly so fluid communication can be established. However, the released pump-out plug needs to be removed from the wellbore, before the retrievable bridge plug assembly can be removed from the wellbore, so it will not interfere with the flow of fluids through the wellbore and to not interfere with the removal of the bridge plug assembly. To retrieve the pump-out plug requires what is commonly called a "fishing job" whereby a special tool is lowered into the wellbore to retrieve the pump-out plug. If the pump-out plug cannot be retrieved in this manner then the pump-out plug has to be milled out by a special milling tool. There exists a need for a device to contain the pump-out plug for ease of retrieval to eliminate the time consuming and costly fishing and/or milling operations.
Various devices have been developed for capturing and containing objects which are released within a wellbore. One such device is described in U.S. Pat. No. 4,182,419 to Yeates, which discloses a downhole surge tool. The surge tool includes a tubular nipple, a surge plug inserted into the nipple, and a catcher subassembly. The catcher subassembly is connected to a lower portion of the nipple and consists of a conventional bull plug with a plurality of fluid communication channels therethrough. When the surge plug in the nipple is displaced by fluid pressure or the like, it falls into the catcher subassembly and there does not interfere with fluid flow in the well. Nowhere is it disclosed or suggested within Yeates to have a plug catcher device which has a bore extending completely therethrough to allow for the free flow of fluids and other objects, such as logging tools and the like, through the device.
Another device designed to capture and contain objects which are released within a wellbore is described in U.S. Pat. No. 4,338,999 to Carter, which discloses a knockout pin trap. The knockout pin trap is mounted in a well casing above a float valve and catches pins falling from the casing installation packers as the pins are broken off by a cementing plug descending into the wellbore. The knockout pin trap consists of a cylindrical hollow body mounted above a float valve and has a plurality of rods extending laterally across its bore and a collapsible pin chute or guide mounted on top of the body to guide the pins into the body. Nowhere is it disclosed or suggested within Carter to have a pump-out plug catcher apparatus which has a bore extending therethrough and which allows the free flow of fluid and objects, such as logging tools and the like, through the apparatus.